1. Field of the Invention
This invention relates to marking devices and is more particularly concerned with rotary head markers for imprint on a moving workpiece, e.g. a strip of bag material, or the like.
2. Prior Art
Rotary head imprinters are used in industry for imprinting indicia on a workpiece such as bag making material in strip form, and the like. A common type of such rotary head imprinters includes a rotatably driven head carrying printing indicia such as type bars with the type exposed at the circumference of the print head for successively contacting an inking roll and then the workpiece which travels on a backing roll. Such imprinters may be associated with a packaging or filling machine or may be employed to imprint the film which is then wound into a roll for subsequent use. This type of imprinter may be employed to imprint small or selected areas of preprinted film panels where the film strip comprises a longitudinally extending series of the panels which will subsequently form individual faces of bags or packages.
With some frequency, it may be necessary to change the type carried by the print head for different imprinting runs. It may also be necessary from time-to-time to vary the size or the transverse location of the imprinting, or the spacing of the imprints along the length of the workpiece such as bag making film strips, or the like.
Heretofore such adjustments have involved complex mechanisms and manipulations with attendant loss of production time, and costly manpower demands.